1. Field of the Invention
The present invention relates to methods for manufacturing elastic wave devices, and elastic wave devices.
2. Description of the Related Art
As a method for manufacturing an elastic wave device, a method as follows has been widely known. That is, in this known method, a plurality of element units are formed on a motherboard which is made of a piezoelectric body, subsequently the motherboard and element units are divided into sections corresponding to each individual element unit, and thus a plurality of elastic wave devices are manufactured in the same manufacturing process. An example of such method is disclosed in International Publication No. WO2012/132147, for example.
In the manufacturing method disclosed in International Publication No. WO2012/132147, a plurality of element units are first formed on a motherboard which is made of a piezoelectric body. In the formation of the element units, a feed line connected to the element units is formed along with the element units. Next, a support layer having projection portions is formed on the motherboard so as to enclose the element units. Subsequently, a cover member is disposed on the support layer. Thereafter, by dividing a thus obtained multilayer body using a dicing tool into sections corresponding to each individual element unit, a plurality of elastic wave devices are manufactured in the same manufacturing process.
As disclosed in International Publication No. WO2012/132147, by providing projection portions on the support layer so as to suppress strain in the frame-like support layer caused by hardening shrinkage, leak defects in the sealing space can be suppressed.
However, with the method for manufacturing an elastic wave device disclosed in International Publication No. WO2012/132147, such a problem occurs in some case that the feed line is separated from the motherboard due to a cutting force of dicing, whereby the feed line cannot be removed. Because of the separation of the feed line electrically connected to the functional elements, there arises a problem that an elastic wave device having a short circuit defect is likely to be manufactured. Further, with the method for manufacturing an elastic wave device disclosed in International Publication No. WO2012/132147, in the case where the number of the projection portions is increased in order to prevent the separation of the feed line, there arises a problem that leak defects are likely to be generated because the projection portions deformed due to the cutting force of dicing consequently deform a support member main body.